A defect in mismatch repair in Saccharomyces cerevisiae stimulates ectopic recombination between homeologous genes by an excision repair dependent process.
A defect in mismatch repair in Saccharomyces cerevisiae stimulates ectopic recombination between homeologous genes by an excision repair dependent process.
复制标题
酿酒酵母中错配修复的缺陷通过依赖于切除修复的过程刺激同源基因之间的异位重组。
DOI：
10.1093/genetics/126.3.535
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发表时间：
1990
期刊：
影响因子：
3.3
通讯作者：
Rothstein,R
中科院分区：
文献类型：
--
作者：
Bailis,AM;Rothstein,R
研究了三个重组和DNA修复基因的突变，以确定它们对酿酒酵母中重复的S-腺苷甲硫氨酸合成酶基因（SAM 1和SAM 2）之间有丝分裂重组的影响。SAM 1和SAM 2分别位于染色体XII和IV上，编码功能上等同但差异调节的AMMet合成酶。这些相似但不相同的基因在核苷酸水平上有83%的同源性，这种同源性仅限于基因的编码区。通过限制性位点切除将单移码突变引入SAM 1的5'端和SAM 2的3'端。这些突变周围的序列与其他基因相应区域的同源性程度显著不同。在野生型遗传背景下，突变的sam基因之间的有丝分裂异位重组以8.4 × 10（-9）的速率发生。在具有较大序列同源性的区域内的标志物的基因转换比在具有相对序列多样性的区域内的标志物的转换更频繁地发生20倍。这两个基因的相对方向阻止了易位的恢复。sam基因之间的有丝分裂重组完全依赖于DNA修复和重组基因RAD 52。错配修复基因PMS 1的突变导致异位重组率增加4.5倍。RAD 1是一种切除修复基因，需要观察这种异位转化率的增加。此外，RAD 1参与调节同源异型染色体基因重组过程中的共转化模式。这些结果表明，错配修复，切除修复和重组修复功能之间的相互作用参与决定异位基因转换频率之间的SAM基因。
Null mutations in three recombination and DNA repair genes were studied to determine their effects on mitotic recombination between the duplicate AdoMet (S-adenosylmethionine) synthetase genes (SAM1 and SAM2) in Saccharomyces cerevisiae. SAM1 and SAM2, located on chromosomes XII and IV, respectively, encode functionally equivalent although differentially regulated AdoMet synthetases. These similar but not identical (homeologous) genes are 83% homologous at the nucleotide level and this identity is limited solely to the coding regions of the genes. Single frameshift mutations were introduced into the 5' end of SAM1 and the 3' end of SAM2 by restriction site ablation. The sequences surrounding these mutations differ significantly in their degree of homology to the corresponding area of the other gene. Mitotic ectopic recombination between the mutant sam genes occurs at a rate of 8.4 x 10(-9) in a wild-type genetic background. Gene conversion of the marker within the region of greater sequence homology occurs 20-fold more frequently than conversion of the marker within the region of relative sequence diversity. The relative orientation of the two genes prevents the recovery of translocations. Mitotic recombination between the sam genes is completely dependent on the DNA repair and recombination gene RAD52. A mutation in PMS1, a mismatch repair gene, causes a 4.5-fold increase in the rate of ectopic recombination. RAD1, an excision repair gene, is required to observe this increased rate of ectopic conversion. In addition, RAD1 is involved in modulating the pattern of coconversion during recombination between the homeologous sam genes. These results suggest that interactions between mismatch repair, excision repair and recombinational repair functions are involved in determining the ectopic gene conversion frequency between the sam genes.
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影响因子：
3.3
作者：
M. S. Williamson;J. Game;S. Fogel
通讯作者：
M. S. Williamson;J. Game;S. Fogel
酿酒酵母中的染色体内重组：反向重复中的相互交换和相关基因转换。
影响因子：
3.3
作者：
Willis,KK;Klein,HL
通讯作者：
Klein,HL
由重复酵母基因之间的高频减数分裂重组产生的染色体易位。
影响因子：
3.3
作者：
Jinks-Robertson,S;Petes,TD
通讯作者：
Petes,TD
染色体内基因转换和重复基因之间序列同质性的维持。
影响因子：
3.3
作者：
Nagylaki,T;Petes,TD
通讯作者：
Petes,TD
不同类型的重组事件由酿酒酵母的 RAD1 和 RAD52 基因控制。
影响因子：
3.3
作者：
Klein,HL
通讯作者：
Klein,HL